Advances in sleep disorders medicine in the last 35 years have resulted in growth of the field from isolated individual physicians to a board-eligible subspecialty organized under the American Academy of Sleep Medicine with several thousand members. Sleep disorders are described and defined in an international classification system now in a second edition. The societal burden of sleep disorders-in addition to burdens arising from insufficient and ill-time sleep-is substantial. At least 10 separate institutes of the NIH currently fund research on diseases of the sleep and/or circadian rhythms systems. Basic sleep and circadian rhythms research have also progressed since the 1970s. The neurobiology of the circadian timing system has been dissected, and the molecular biology of circadian timing is unraveling as scientists use a variety of methods and organisms to identify key molecular components. Indeed, these advances has led to gene associations for circadian rhythms disorders, in particular the familial advanced sleep phase syndrome (FASPS). Recent progress has occurred in the molecular biology of sleep and sleep disorders. An important advance has come from the identification of sleep (or sleep-like behavior) in model systems, such as the fruit fly and in gene expression approaches. Scientists studying narcolepsy, a sleep disorder affecting humans and genetically transmitted in dogs, exposed an previously unknown neural system through genetic studies. The need for additional methods for gene association studies by investigators and clinicians in human sleep and circadian rhythms laboratories is now apparent. One approach used in other fields, e.g., alcohol and addiction studies, is to develop a targeted gene chip. Whether the sleep/circadian rhythms field is ready to take advantage of this method is uncertain. To examine this issue, a workshop will assess feasibility, identify parallel or alternative approaches, and make strides to prepare the community for such approaches. Investigators engaged in gene discovery in the sleep and circadian rhythms areas, clinicians whose knowledge of sleep disorders amenable to genetic approaches, human sleep researchers who have obtained phenotypic data from humans, and scientists engaged in gene chip research in other fields will come together to address these questions. This goal of this project is to hold a workshop for scientists and clinicians to examine a new method for performing genetic studies that may advance understanding of sleep disorders and sleep/wake patterns in humans. The technique that will be the focus of the workshop is a gene chip that would include genes thought to be important to regulating sleeping and waking. The workshop will also examine other methods and techniques that may help advance the genetic study of sleep and sleep disorders. [unreadable] [unreadable] [unreadable]